Cannot use LWPCookiejar with requests

[hramrach]

There is no way to put cookies into a standard cookiejar.

Expected Result

Cookies can be stored in LWP format

Actual Result

Cookies are provided in multiple unusable formats, no way to store to a standard jar.

Reproduction Steps

Make a request that returns multiple cookies. (This is not verified, I do not know how to access actual headers from a Response object.)

        r = requests.request(method, self.url + path, *args, **kwargs)
        if hasattr(self, 'cookiejar'):
            if 'Set-Cookie' in r.headers or 'Set-Cookie2' in r.headers:
                def get_all(self, name, default=[]):
                    return [self.get(name, default)]  # it's a dictionary, can only have one match anyway
                if not hasattr(r.headers, 'get_all'):
                    r.headers.get_all = types.MethodType(get_all, r.headers)

                self.cookiejar.extract_cookies(requests.cookies.MockResponse(r.headers),
                                               requests.cookies.MockRequest(r.request))

Response has a cookies property but this returns a custom cookie jar which cannot be saved in LWP format.

The standard LWPCookieJar provides interface for iterating cookies but not storing cookies, only for extracting cookies from headers.

The Response object has a headers property but this is a dictionary, and cannot store multiple headers of the same name correctly. There is nothing stopping the server from sending multiple Set-Cookie headers, the standard only requests that no two cookies with the same name be sent. When it does the Response headers property has a mangled Set-Cookie header, and it cannot be parsed by LWPCookieJar. Response does not provide access to unmangled headers in any way I can find in the documentation.

System Information

Linux, python 3.6~3.11

{
  "chardet": {
    "version": null
  },
  "charset_normalizer": {
    "version": "3.1.0"
  },
  "cryptography": {
    "version": "41.0.3"
  },
  "idna": {
    "version": "3.4"
  },
  "implementation": {
    "name": "CPython",
    "version": "3.11.13"
  },
  "platform": {
    "release": "6.4.0-150600.23.47-default",
    "system": "Linux"
  },
  "pyOpenSSL": {
    "openssl_version": "30100040",
    "version": "23.2.0"
  },
  "requests": {
    "version": "2.31.0"
  },
  "system_ssl": {
    "version": "30100040"
  },
  "urllib3": {
    "version": "2.0.7"
  },
  "using_charset_normalizer": true,
  "using_pyopenssl": true
}

[hramrach]

https://datatracker.ietf.org/doc/html/rfc7230#section-3.2.2 notes that Set-Cookie fields are an exception to the rule that fields of the same name can be appended. And that seems to be exactly what is happening here. The Set-Cookie fields are appended leading to an invalid header, and inability to parse the cookies.

[BharathC0]

@hramrach will you please assign to me

[hramrach]

        r = requests.request(method, self.url + path, *args, **kwargs)
        if hasattr(self, 'cookiejar'):
            if 'Set-Cookie' in r.headers or 'Set-Cookie2' in r.headers:
                if not hasattr(r.headers, 'get_all'):
                    headers = email.message.EmailMessage(policy=email.policy.HTTP)
                    for k in r.headers.keys():
                        if k.lower() == 'set-cookie' or k.lower() == 'set-ccokie2':
                            cookies = r.headers[k].split(',')  # https://github.com/psf/requests/issues/7014
                            for c in cookies:
                                headers[k] = c
                        headers[k] = r.headers[k]
                else:
                    headers = r.headers

                self.cookiejar.extract_cookies(requests.cookies.MockResponse(headers),
                                               requests.cookies.MockRequest(r.request))

Works perfectly when cookies happen to be comma-free (not aware of anything preventing fields like path or expire from containing commas).

https://github.com/alexdutton/www-authenticate could be probably massaged to cover most cases but if the headers field was constructed as EmailMessage to start with this would just work. That's even what MockResponse expects and it fails when the custom dictionary used for headers is passed in. To not break other users that rely on concatenated headers the headers other than cookies can still be concatenated.

[hramrach]

I do not have the permissions to assign